Well, word from Dave Roth is that this is now on his ever-growing list of things to fix. So, no joy for me...back to my workaround of shelling out and running an external program to get this attribute. Thanks to those who /msg'd me with suggestions!

"One word of warning: if you meet a bunch of Perl programmers on the bus or something, don't look them in the eye. They've been known to try to convert the young into Perl monks." - Frank Willison